1. Technical Field
The present disclosure generally relates to printed circuit boards (PCBs), and particularly relates to a printed circuit board and a method for manufacturing the printed circuit board.
2. Description of Related Art
To accommodate development of miniaturized electronic products with multiple functions, printed circuit boards are widely used.
A PCB usually needs a plurality of blind vias for electrically connecting two trace layers or more than two trace layers. In a method of manufacturing the PCB, a dielectric layer is laminated on a circuit substrate with at least one pad, and at least one first opening is defined in the dielectric layer by laser. Each first opening corresponds to one pad. Then, a photoresist pattern is formed on the dielectric layer, and at least one second opening is defined in the photoresist pattern by exposing and developing process. Each second opening must be aligned with a corresponding first opening. Finally, conductive metal material is formed in the first and second openings, thus, a blind via are formed. In order to easily achieve the alignment and each first opening is entirely exposed at the corresponding second opening, the second opening is larger than the first openings. Accordingly, a distribution density of the second openings is smaller, and a distribution density of the teace is also smaller.
What is needed therefore is a printed circuit board, and a method for manufacturing the printed circuit board to overcome the described limitations.